This invention relates to floor burnishers, and particularly to floor burnishers of the power cord type.
Burnishers for maintenance of floor services are known to have pad undersurface configurations that create a negative pressure thereunder during high speed rotation to thereby cause the burnisher, and therefore the burnishing pad, to lower and vigorously engage the floor surface while the burnisher is advanced over the floor surface. Floor surfaces are frequently less than perfectly level, however, having higher areas and lower areas. As conventional burnishers move across higher areas, the power required to operate the electric motor which rotationally drives the burnisher pad can readily increase from about 15 amperes up to 22 amperes, or in some situations even 30 amperes. This tremendous and sudden variation in power level demand can be troublesome to the electrical system as well as demanding on the motor windings.
Some burnishers have mechanisms for adjusting the height of the mechanism so as to somewhat regulate the extent to which the pad engages the floor, and thereby try to control excessive amperage variations. However, this does not significantly remove the difficulty since the choice is then between less than vigorous engagement with the floor and more effective engagement along with large amperage variations. Moreover, this adjustment is usually difficult to achieve with prior burnishers whether cord or battery type. The motor is fixed to the housing so that, with adjustment, the pad will be positioned at an angle to the floor rather than parallel to the floor. This is undesirable.